Work support for grinding machines



Aug. 11, 1925.

c. KNOWLES WORK SUPPORT FOR GRINDING MACHINES Filed Au. '2. 1922' 2-sBeets-sneez 1 INVENTQR- ATTORNEY Aug. 1.1, 1925.

C.- KNOWLES WORK SUPPORT FOR GRINDING MAQHINES Filed Aug. '7. 1922 2 Sheets-Shit". 2

INVENTOR moamwm ATTORNEY Patented Aug, ll, 1925.

UNITED ST'l'ES j-klhhl'l CARROLL KNOWLES, 0F HARTFORD, CONNECTICUT, ASSIGNOB IE0 PRATT & WHITNEY COMPANY, 019 NEW YORK, N. 53., A COEPGRATION OF NEW JERSEY.

WORK SUPPQRT FOR GRINDING MACHINES.

Application filed August 7, 1922.

To all w/zom it may concern:

Be it known that I, CARROLL KNowLns. a citizen of the United States, residing at Hartford, in the county of Hartford and State of Connecticut, have invented certain new and useful Improvements in Work Supports for Grinding Machines, of which the following is a specification.

This invention relates to a back rest or work support for cylindrical grinding machines and in particular to an automatically operated back rest to uniformly support the work during the progress of the grinding operation.

An object of the present invention is to provide a movable back rest or supporting means for cylindrical work being ground which will engage a part of the work oppo-site that engaged by the abrasive wheel, and which will be positively moved to continuously engage and support the work as the wheel advances and reduces the diametcr oi? the work during" the grinding operation.

Qne feature which enables me to accomplish the above named object is that the back rest or work supporting member may be oscillated about a pivot, means being provided to positively oscillate it toward the work axis while the wheel is in contact with the work during; the grinding operation.

.Jtnother feature of novelty which is advantageous is that means are provided which are directly movable with the wheel slide so that as the wheel slide advances dur ng the grinding operation a lever or other mem her is operated to positively oscillate the back rest or work support toward the axis of the work.

Another object of the present invention is to provide means so that the work will be positively supported at all times while the abrasive wheel is in contact with the work, and, as the wheel slide requires to be advanced slightly to compensate for wheel wear the actuating means for the back rest or work support may be maintained in position so that it will always be moved into the same predetermined position to properly engage and support the work.

A further object of the invention is to provide means to withdraw the work support from engagement with the work when the wheel and wheel slide are moved to their inoperative positions.

Serial No. 580,266.

A still further object of the invention is to provide a back rest or work support that can be conveniently adjusted for different dian'ieters of work. Preferably this adjustment may be accomplished independently of the adjustment of the wheel slide.

The construction described and claimed in this application is adapted particularly for a machine such as shown and described in my copending application, Serial No. 587,- filed on September 9, 1922, to which reference may be had for a detailed description oi the mechanisms forming the machine.

Preferably, this work support or back rest may be conveniently mounted on the work table in such a manner that it may be positively oscillated toward the work by movement of the wheel slide into work engaging position. Movement of the work support away from the work is preferably accomplished by a spring so that as soon as the wheel is moved to its inoperative position the support is simultaneously withdrawn.

also the work support or back rest preferably may be associated with a teeler mechanism adapted to contact directly with the work and operate an automatic device to slightly feed the wheel when it has become worn or to indicate completion of the grinding' operation when the work has been reduced to a predetermined diameter.

A further and principal object of the invention is to provide a back rest or work support acting positively to support the work throughout the entire grinding operation and which, when once adjusted, may he used for any chosen diameter of work and will enable unittorm work to be produced in a grinding machine with a mini mum of inspection.

l Vith these and other objects in view, my invention consists in the features of construction and operation set forth in the following specification and illustrated in the accompanying drawings.

In the accompanying drawings annexed hereto and forming a part of the specification, I have shown my invention embodied in an automatic cylindrical grinding machine having; a. wheel substantially as wide as the work being ground, but it will be understood that the invention can be otherwise embodied and that the drawings are not to be construed as defining or limiting the scope of the invention, the claims appended to this specification being relied upon for that purpose.

In the drawings:

Figure 1 is a side view of the back rest or work support shown in operative position relative to the work and grinding wheel.

Fig. 2 is a front view of a portion of a cylindrical grinding machine provided with the present invention, the wheel and slide being omitted.

Fig. 3 is a view similar to Fig. 1 on an enlarged scale, parts being broken away to more clearly show the construction.

Fig. 1 is a front sectional view taken on line 44 of Fig. 3.

Fig. 5 is a plan view of the invention.

Fig. 6 is a detail view of the back rest or work support in its retracted position.

In the above mentioned drawings, 1 have shown but one embodiment of the invention which is now deemed preferable but it is to be understood that changes and modifications may be made within the scope of the appended claims without departing from the spirit of the invention.

Briefly, my invention in its broadest aspect comprises the following principal parts: first, a cylindrical grinding machine having the usual movable work table; second, a wheel slide carrying a rotatable abrasive wheel adapted to be moved toward or away from the axis of the work; third, a support preferably mounted on the work table; fourth, an oscillating back rest or work support mounted on this support; fifth, a member outstanding from and moving with the wheel slide adapted to advance the back rest during the grinding operation in accordance with the advancing movements of the wheel; and sixth, adjusting means for the actuating member outstanding from the wheel slide and for the oscillating member to adapt the back rest for different diameters of work and to compensate for wheel wear.

Referring more in detail to the figures of the drawings, I show a portion of a special form of broad wheel automatic cylindrical grinding machine 10 having a work table 11 which may be movable longitudinally along the base 10 and on which is mounted a headstock 12 and tailstock 13 for supporting and rotating the work. In rear of the work table 11 is a wheel slide 141- automatically movable at right angles to the direction of movement of the work table 11 so that it may be moved directly toward or away from the axis of the work A at the appropriate time during the cycle of operation of the machine. Upon the wheel slide 14: is a rotatable abrasive wheel 15 of the usual type, the position of which relative to the work A for different diameters of work blanks A may be varied by adjustment of a nut 16 on the wheel slide screw 17. In addition special automatically operating means are provided for advancing and retracting the wheel support or slide 14- as by means of the rod 31- so that the wheel is moved into engagement with the work A during operation and out of en gagement when the work is being changed. These means are shown more fully in Fig. 8 of application 587,158 referred to above. All of the above parts are similar to those of my copending application above mentioned and for that reason will not be further described.

Disposed between the headstock 12 and the tailstock 115 and adjustably mounted on the work table 11. is a support 20 which is provided with two upright side members 21 having a short transverse shaft 22 extending between them near their upper ends. About this shaft 22 a member 21- is disposed between the two side members 21 which is adapted to be oscillated in accordance with ll'lOVQl'l'lOlltS imparted to it in a manner presently to be described. A coiled spring 25 is attached at one end to the adjustable support 20 on the work table 11 and at its 0pposite end to the oscillating member 2 1-. By this means the oscillating member 21 is normally held in retracted position when it is not being positively advanced toward its work engaging position.

iilounted on this oscillating member 21 in s tatably mounted work is a bearing block 26 which may be adjustably positioned and irped on surface provided on the oscil- 7 member. To adjust this block in suitable positions for different diameters of work and to retain it in adjusted position, screws 27, 27 and 27 are provir ed.

The lower surface of the oscillating member 24.- is arcuate and provided with a number of gear t eth 29, thus forming a seg mental gear. Below and in contact with the oscillating member 24: is an arm 30 .l'ried to the shaft 31 provided in the support 20 parallel to the shaft or rod 22 about which the member 2aoscillates. The upper end of this arm 30 is provided with gear teeth 3.. adapted to interniesh with the gear teeth 29' on the oscillating member 24:. Attached to and extending below the axis of oscillation of this arm 30 is an arm 33 adapted to be engaged by a member or rod 23-41: extending through and outstanding from the wheel slide 14.

It will be seen from the above description that as the wheel 15 and wheel slide 14: are advanced automatically toward the axis of the work A while the wheel is being moved into operative position, and during the grinding operation, the rod 34- outstanding from the wheel slide 141. will engage the lower end of the oscillating arm 33 and, by oscillation of this arm 33, will correspondingly oscillate the arm 30 and the member 24 held within the support 20.

Thus, the work contacting or bearing block 26 on the oscillating member 24 forming the work support will be advanced toward the work A and will be continuously held in engagement therewith during the grinding operation. The arrangement of the oscillating member 24 and the proportions of the arms 81 and 33 are such that the movement of the work bearing block 26 during the grinding operation toward the axis of the work A is equal to the advancing movement of the wheel 15.

The member or rod 34 outstanding from the wheel slide is provided with an adjustable end piece 35, the distance from the wheel slide 14 of which may be varied by rotation of the graduated dial 36, as shown. This serves to slightly increase or decrease the length of the rod 34 in advance of the forward grinding surface of the abrasive wheel 15 and permits adjustments of the work support 24 to be readily made during operation, or while the machine is being set up to properly locate the bearing block 26 relative to the work A. This adjustment is made use oi also to compensate for the wearing away of the surface or the bearing block 26. It will be seen that by increasing the cll'ective length of the rod 34 an amount corresponding to the amount the bearing block 26 is worn away during the operation, that the bearing block 26 on the oscillating member 24 will be readily retained in exactly the same predetermined position relative to the axis of rotation of the work A.

It will be seen in Fig. 1 that the forward end of the rod 84 outstanding from the wheel slide 14, which is automatically moved to control the position of the wheel slide, is mounted on the wheel slide adjusting screw, the threaded portion of which is surrounded by the nut 16. Adjustment 01 this nut 16 is made use of to vary the position of the wheel slide 14 and wheel 15 with reference to the automatically determined position. oi the rod 84 and wheel slide 14 for differcnt diameters of work A being ground. It will also be seen that this adjustment of the wheel 15 for different diameters does not prevent other adjustments of the rod 34 as by the extension 35 to accommodate the back rest and bearing block 26 for slightly different sizes of work or to compensate for wheel wear and wearing of the block 26. Also, when the slide 14 and the oscillating member 24 have been adjusted for different diameters of work A, the mechanism as sures that the bearing block 26 will be retained in proper operative position during grinding operations on a large number of: articles and that the work will all be ground to identical diameters.

The movable back rest or work support 24 has been shown mounted adjacent a feeler mechanism 40 for indicating when the work piece A has been reduced to a predetermined diameter and the grinding operation thereon completed. This, as shown, comprises a a lever 41 preferably, but not necessarily, oscillating about the same axis 22 as the back rest 24 and having one arm 42 extending toward the axis upon which the work A. is mounted and rotated. t the end of this arm is a contact member 43 which may be in the form of a diamond, or any hard substance, which will not appreciably wear during operation. The other arm 44 of this lever 41 is weighted so that it normally holds the work contacting arm 42 of the lever 41 toward the axis 01 the work A and, at the outer end of this latter arm 44, is an adjustably mounted member 45 adapted to engage and oscillate a pivotally mounted arm 46.

The arm 46 adapted to be oscillated by this member 45 is supported by means oi thin flexible steel strips 47 positioned at right angles to each other so that the arm 46 may be oscillated slightly about a hori zontal axis represented by the intersection of the planes ot the flexible strips. The free end of this arm 46 which preferably is vertically disposed lies adjacent an adjustable contact 48, the position of which may be varied by rotation of the graduated dial 49, shown. it will thus be seen from this construction that the oscillating lever 41. when it finally is moved to a predetermined point represented by the predetermined size of the articles A. being ground, will cause the vertical arm 46 to oscillate slightly away from the adjustable contact. This position shown in Fig. 8. An electric circuit 111-- cluding the adjustable contact 48 and the oscillating arm 46 is then interrupted, which break of the circuit may be used to operate a signal to indicate the completion of the work or to automatically readjust the position of the wheel slide 14 to compensate for wheel wear. lit will be seen also that until the work A has been reduced accurately to a final predetermined diameter the oscillating arm 46 and adjustable contact 48 will be maintained in contact and thus the circuit will remain closed.

Special means are disclosed in the copendin g application 587,158 for compensating for the wearing away of the wheel. These means are shown in Fig. 10 of the above mentioned application and act upon the worm in mesh "ith worm wheel 16 of the present application. The movement forward and backward of the wheel during operation is always a constant amount and is controlled by mechanism clearly described in the copending application above mentioned As it is essential in the embodiment of the invention illustrated to withdraw the feelermember 43 and arm 42 from adjacent the snark A while work pieces are being changed, a hook member outstanding from the oscillating work support 52 is providec v l .l I "x lhis engages tne ieeler arm e2 oi the OSClllating lever -l1 so that when the work support 24- is withdrawn from adjacent the axis of the work A, the leeler arm -l-2 is also removed. Also, wnen the work support 2i is again oscillated into operative position by movement of the wheel slide 1%, the feeler arm 4-2 is permitted to oscillate into contact with the work.

hat I claim is 1. A back rest for cylindrical grinding machines comprising in combination, a support, a movable member thereon adapted to contact with and support work being ground in operative position during the grinding operation, and means directly attached to and movable with the wheel slide to maintain said movable member in contact with the work while said wheel is in engagement with and operating on said work.

2. A back rest for cylindrical grinding machines comprising in combination, a support, a movable member thereon adapted to contact with and support work being around in operative position during the rinding operation, and adjustable means attached to and movable with the wheel slide to main-- tain said movable member in contact with the work while said wheel is in engagement with and operating on said work.

3. A back rest for cylindrical grinding machines comprising in combination, a support, a movable member thereon adapted to contact with and support work being ground in operative position during the grinding operation, means directly attached to and movable with the wheel slide to maintain said movable member in contact with the work while said wheel is in engagement with and operating on said work, and means to withdraw the movable member when the wheel is moved away from the work.

l. A back rest for cylindrical grinding machines comprising in combination, a support, a movable member thereon adapted to contact with and support work being ground in operative position during the grinding operation, adj List-able means attached to and movable with the wheel slide to maintain said movable member in contact with he work while said wheel is in engagement with and operating on said work, and means to withdraw the movable member when the wheel is moved away from the work.

5. it back rest for cylindrical grinding machines comprising in combination, a support, an oscillating member thereon adapted to contact with and support work being ground in operative position during the grinding operation, and adjustable means directly attached to and moved with the wheel slide to maintain said oscillating in contact with the work while said Q lZ. nga ement with 1 id operating well-I. ii back rest for cylindrical grinding machines comprising in combination, a support, a n'iovable member thereon adapter to contact with and support work being ground in operative position, and means movable with the wheel slide 01" the machine for moving the member into work engaging position as the wheel advances toward the work.

T. A back rest for cylindrical grinding machines comprising in con'ibination, a supmorable member thereon adapted to t with and support work being ground in o erative position, and means movable with tl e wheel slide of the machine to]: positively moving the member into work cir- ,aging position as the wheel advances toward the work.

port, a

8. fr back rest For cylindrical grinding machines comprising in COHllJlDzItlOIl, a support, a movable n'ien'iber thereon adapted to contact with and support work being ground in operative position, means movable with the wheel slide of the machine for positively moving the member into work engaging position as the wheel advances toward the work, and spring means to withdraw the m vabie member when the wheel is moved away from the work.

9. A back rest for cylindrical grinding machines comprising in combination, a support, a movable member thereon adapted to contact with and support work being ground in operative position, and means movable with the wheel slide oi the machine for moving the member into engagen'ient with the work as the wheel advances and for main taining the member in engagement there with during the ding operation.

10. it back rest for cylindrical grinding machines comprising in coii'ibination, a sup port, a movable member thereon adapted to contact with and support work being ground in operative position, and means movable with the wheel slide of the machine for p0sitively moving the member into engagement with the work as the wheel advances and for positively maintaining the member in engagement therewith during the grinding oporation.

ll. A back rest for cylindrical grinding machines comprising in combination. a support, a movable member thereon adapted to contact with and support work being ground in operative position, and means movable with the wheel slide oi? the machine for moving the member into work engaging position as the wheel advances toward the work, said means being adjustable to compensate for wear of some of the parts of the mechanism.

12. it back rest for grinding machines comprising in combination, a support, a movable member thereon adapted to contact ion with and support work being ground in operative position, a se mental gear thereon, a segmental gear in engagement with said first gear, and means movable with the wheel slide of the machine for oscillating said gears and moving the member into engaging position as the wheel advances toward the work.

13. A. back rest for grinding machines comprising in combination, a support, a movable member thereon adapted to contact with and support the work during the grinding operation, a segmental gear thereon, a segmental gear in engagement with said first gear, means movable with the wheel slide of the machine for oscillating said gears and moving the member into engaging position as the wheel advances toward the work, and means to withdraw the member as the wheel is moved away from the work.

ll. A back rest for grinding machines comprising in combination, a support, a movable member thereon adapted to contact with and support the work during the grinding operation, a segmental gear thereon, a segmental gear in engagement with said first gear, and means movable with the wheel slide of the machine for oscillating said gears and moving the member into engaging position as the wheel advances toward the work, said means permitting withdrawal 01. said member from work engaging position as the wheel is moved away from the work.

15. A back rest for grinding machines comprising in combination, a support, an oscillating member thereon adapted to contact with and support the work during the grinding operation, a segmental gear here on, a segmental gear in engagement with said first gear, and means for oscillating said gears and member into and out of engaging position with the work in accordance with movements of the wheel relative to the work.

16. A cylindrical grinding machine comprising in combination, a base, a wheel slide having an abrasive wheel rotatably mounted thereon, work supporting and rotating means on said base, a movable back rest for the work, means to move said wheel toward and from the work, and means operated simultaneously with movement of the wheel toward the work to positively advance said back rest toward the work.

17. A cylindrical grinding machine comprising in combination, a base, a wheel slide having an abrasive wheel rotatably mounted thereon, work supporting and rotating means on said base, a movable back rest for the work, means to move said wheel toward and from the work, and means operated simultaneously with movement of the wheel toward the work to positively advance said back rest and maintain it in contact with the work during the grinding operation.

18. A cylindrical grinding machine comprising in combination, a base, a wheel slide having an abrasive wheel rotatably mounted thereon, work supporting and rotating means on said base, a movable back rest for the work, means to move said wheel toward and from the work, and means operated by movement 01 the wheel toward the work to positively advance said back rest and main tain it in contact with the work during the grinding operation.

19. A. cylindrical grinding machine comprising in combination, a base, a wheel slide having an abrasive wheel rotatably mounted thereon, work supporting and rotating means on said base, a movable back rest for the work, means to move said wheel toward and from the work, and means op erated simultaneously with movement of the wheel toward the work to positively advance said back rest toward the work, said means being adjustable for work of different diameters.

20. A cylindrical grinding machine comprising in combination, a base, a wheel slide having an abrasive wheel rotatably mounted thereon, work supporting and rotating means on said base, a movable back rest for the work, means to move said abrasive wheel toward and from the work, and means 0perated by movement of the wheel toward the work to positively advance said back rest toward the work and maintain it in operative position during the grinding operation.

In testimony whereof, I hereto aftix my signature.

CARROLL KNOWLES. 

